Stack gas emissions of PCDD/Fs from hospital waste incinerators in China

Stack gas samples from 14 domestic-made hospital waste incinerators (HWIs) in China were collected and analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The waste burning capacities of the investigated HWIs ranged from 5 to 25 ton d(-1). The stack gas emissions of PCDD/Fs from HWIs exhibited a large variation (0.08-31.60 ng I-TEQNm(-3)). Nine incinerators had the emission levels below the current emission standard in China (0.5 ng I-TEQN m(-3)), while only two facilities exhibited emission levels below the European Union directive emission limit (0.1 ng I-TEQN m(-3)). For two plants, concentrations of PCDD/Fs in stack gas were above 10.0 ng I-TEQN m(-3). The emission factors of PCDD/Fs from the investigated HWIs were in the range of 0.78-473.97 microg I-TEQ ton(-1) medical wastes. It was estimated that 4.87 g I-TEQ of PCDD/Fs was annually released from HWIs to the atmosphere in China in 2006. Principal component analysis and hierarchical cluster analysis were applied to analyze the congener profiles of PCDD/Fs from HWIs in China.